[j-nsp] Finding drops

[Jason Lixfeld]

This is somewhat embarrassing. I was looking at the wrong side of the test when I initially observed the issue and I didn’t clue into that till now, so some of the previous claims are false.

Just for completeness, here’s the actual test topology:

[ Tx Tester ] - et-0/0/2 - [ mx1 ] - et-0/0/0 - [ mx2 ] - et-0/0/2 - [ Rx Tester ]

...

> On Jan 23, 2019, at 8:58 AM, Saku Ytti <saku at ytti.fi> wrote:
> 
> On Tue, 22 Jan 2019 at 20:17, Jason Lixfeld <jason-jnsp at lixfeld.ca> wrote:
> 
> 
>> Transmitting exactly 100 million 64 byte UDP packets.  SPORT:  49184 DPORT: 7.
> 
> Ok so ingress interface shows 100M packets coming in, but egress
> interface shows only 76M packets going out?

Not quite.  Tester is sending 100M packets, ingress interface (et-0/0/2 @ mx1) shows 86 million packets coming in

> And nothing in  'show int egress extensive'?

Now that I’m looking at the right box, yes!  More importantly, on et-0/0/2 @ mx1:

…
  Traffic statistics:
   Input  packets:             85405847                    0 pps
…
  Input errors:
    Errors: 0, Drops: 0, Framing errors: 0, Runts: 0, Policed discards: 0, L3 incompletes: 0, L2 channel errors: 0, L2 mismatch timeouts: 0, FIFO errors: 0, Resource errors: 14594154
…

85405847+14594154 = 100000001

So now I see an error counter that has incremented and that accounts for the missing packets.  This is what I was after.



Incidentally, Olivier brought up hyper mode, so here are the results of that.

et-0/0/2 @ mx1:
…
  Traffic statistics:
   Input  packets:            100000017                    0 pps

et-0/0/0 @ mx1:
…
  Traffic statistics:
   Output packets:             76645888                    8 pps
…
 Output errors:
    Carrier transitions: 1, Errors: 0, Drops: 23355576, Collisions: 0, Aged packets: 0, FIFO errors: 0, HS link CRC errors: 0, MTU errors: 0, Resource errors: 0
  Egress queues: 8 supported, 4 in use
  Queue counters:       Queued packets  Transmitted packets      Dropped packets
    0                        100000097             76644521             23355576
    1                                0                    0                    0
    2                                0                    0                    0
    3                             1348                 1348                    0

Thanks all!  Now I can try and look into those error counters.